ADS L1590

[Glitch]

18 hours ago, tysontom said:

I think the different crossovers and slight differences between the 2-inch dome midrange drivers between the two speakers probably accounts somewhat for the difference in perceived transient performance.  Except for the more robust L1590 woofers, I don't understand why the L1590 has greater overall power-handling capability than the L1290, especially since the 2-inch dome is driven to a lower crossover frequency in the big speaker.  How this could represent greater power-handling, I don't know!  The upper end should be equal across the board.  Thoughts?

The L1590 has different tweeters, mids and woofers than the L1290.  I assume that each one of the components in the L1590 is rated for more power, but can't find any data right now to back up my theory. 

18 hours ago, tysontom said:

Also, do you have any copies of your measurements on these speakers?  I would love to see them if you have saved any.  If you could do some impulse tests—even the old transient-response tests—it would be interesting to see if there are any differences in the two speakers' midrange performance.

I'm sure that I have data from the L1290 and L880 drivers somewhere on my computer.  Unfortunately, I'm pretty thorough at testing and analyzing data, but usually not very good at documenting the results.  If I found the data, it might not be clear what I actually tested.

It all may be a moot point since I tested individual drivers from the L1290 and L880, but didn't disassemble the L1590 for individual driver testing.  My comparisons between the L1290 and L1590 were done with the speakers side by side connected to a speaker selector switch.  In the past, I've tried to run quantitative comparisons of overall speaker performance, but never obtained results that I thought I could trust.  I typically end up doing qualitative evaluations (which may be too subjective to be useful to anyone else).

18 hours ago, tysontom said:

I would not think so, as both use the same magnet and voice-coil assemblies.

I recall reading somewhere that the L1590 mids and tweeters had stronger magnets than the L1290.  However, I can't recall where I read that.

18 hours ago, tysontom said:

Did you actually find the Ferrofluid dried up in the 1290s?  Was it partially dry or what was the case?

I've only experienced one ADS driver with a ferrofluid issue.  The best way I can describe it is that the fluid "crusted over".  The fluid under the crust seemed fine.  I originally repaired the driver by cleaning out all of the dried fluid "chunks" and running the driver with the remaining fluid.  I've since completely replaced the fluid (several times) in the course of my various experiments.

18 hours ago, tysontom said:

Also, as for imaging, I would think that the L1290 and L890 speakers, with their higher midrange crossover, might image slightly better than the 1590, but the latter would have somewhat greater "spaciousness" in the reverberant field.  More three-dimensional in the far field.

I believe that improvements in imaging in my L1290 (and L880) were more from using matched driver pairs than anything else.  I'd love to be able to repeat the driver matching experiment on the L1590s, but I don't have a suitable pool of spare parts to make it happen.

19 hours ago, tysontom said:

These were all great speakers!  Do you also have a pair of L980s?

Unfortunately, no.  There are only a couple of ADS speakers that are on my watch list and the L980 is one of them.

 

[tysontom]

Hi Glitch,

Great message.  Regarding the L980s, I wonder how it would compare, ultimately, with the AR-3a?  There would be a fairly close resemblance in terms of bandwidth and spectral balance, except that the ADS speakers would have noticeably greater upper-midrange and treble output in comparison with the AR-3a.  As for accuracy, it would be a close call, with both speakers representing a very high level of smoothness and low distortion.

I am quite surprised that at least one of ADS's later designs didn't make it to Stereophile magazine's "Best Top Speakers of the Past 40 Years."  You just never know how these things will go, but there were several ADS speaker that could easily have outmatched several of the magazine's top picks.  Of course, Stereophile magazine (much like TAS) reviews and articles were heavily weighed on subjective evaluation and judgment, and the results were usually more emotional than objective.  

https://www.stereophile.com/content/40-years-istereophilei-hot-100-products-page-7

By the way, you are exactly right about the different part numbers for the ADS 1590 and 1290!  For some reason I thought the tweeters were identical, but it's not the case.  According to what I found in my files: 

L1290: tweeter 206-0117, mid 206-0211, woofer 206-0349

L1590: tweeter 206-0119, mid 206-0213, woofer 206-0350.

I'm not positive that these are the Series 2 part numbers or the original series, but I think so.  You may know for sure.

--Tom 

[Glitch]

6 hours ago, tysontom said:

Regarding the L980s, I wonder how it would compare, ultimately, with the AR-3a?

Setting up a listening comparison between those two speakers would be a real treat.  I have neither, so it could be a long while until I have the opportunity.  Based on my experience with the L1590, L1290 and L880, I would think that you would be able to A/B your 3a's and L1290's and get a very good feel for how they stack up.  The tricky part of the experiment might be getting the room setup right since each of those speakers would have a fairly different "ideal" spot in the room.  I'm guessing that you already thought of this and is one of the reasons why you suggested the 3a to L980 comparison.  (i.e. both would benefit from a similar setup position, etc.).

The Stereophile Magazine article was a trip down memory lane.  To me, it seems "right" that there weren't any ADS offerings on the list.  I've never thought of ADS as one of those companies that was targeting the stereotypical audiophile personality.  Sure, there were other companies on the list that are arguably similar in this regard.  IMHO, there products were more revolutionary than anything ADS did.  As big of an ADS fan as I am, I don't feel slighted at all by the list.

Here are some relevant part numbers (from the ADS parts list)

L880:       tweeter 206-0117, mid 206-0211, woofer 206-0346

L880/2:   tweeter 206-0117, mid 206-0215, woofer 206-0357

L1290:     tweeter 206-0117, mid 206-0211, woofer 206-0349

L1290/2: tweeter 206-0117, mid 206-0215, woofer 206-0359 or 206-0360

L980:       tweeter 206-0118, mid 206-0212, woofer 206-0347

L980/2:   tweeter 206-0118, mid 206-0214, woofer 206-0353

L1590:     tweeter 206-0119, mid 206-0213, woofer 206-0350

L1590/2: tweeter 206-0118, mid 206-0214, woofer 206-0361

I'm a bit surprised that drivers pattern on the L980/L1590 doesn't follow the same pattern as the L880/L1290.  I wonder if the L980 was introduced "late" relative to the L1590? (i.e I expected that it, L980/1, would have a 206-0119 tweeter & 206-0213 mid)

 

[batchman]

So I guess I had mis-remembered this.  My 1590s and 980s are both series 1, so they aren't identical (mid/tweet) drivers after all.  Drat.

Not going to try to "cure" that though!

 

Best,

- Jeff

 

[tysontom]

On 6/5/2018 at 8:07 PM, Glitch said:

Setting up a listening comparison between those two speakers would be a real treat.  I have neither, so it could be a long while until I have the opportunity.  Based on my experience with the L1590, L1290 and L880, I would think that you would be able to A/B your 3a's and L1290's and get a very good feel for how they stack up.  The tricky part of the experiment might be getting the room setup right since each of those speakers would have a fairly different "ideal" spot in the room.  I'm guessing that you already thought of this and is one of the reasons why you suggested the 3a to L980 comparison.  (i.e. both would benefit from a similar setup position, etc.).

The Stereophile Magazine article was a trip down memory lane.  To me, it seems "right" that there weren't any ADS offerings on the list.  I've never thought of ADS as one of those companies that was targeting the stereotypical audiophile personality.  Sure, there were other companies on the list that are arguably similar in this regard.  IMHO, there products were more revolutionary than anything ADS did.  As big of an ADS fan as I am, I don't feel slighted at all by the list.

Here are some relevant part numbers (from the ADS parts list)

L880:       tweeter 206-0117, mid 206-0211, woofer 206-0346

L880/2:   tweeter 206-0117, mid 206-0215, woofer 206-0357

L1290:     tweeter 206-0117, mid 206-0211, woofer 206-0349

L1290/2: tweeter 206-0117, mid 206-0215, woofer 206-0359 or 206-0360

L980:       tweeter 206-0118, mid 206-0212, woofer 206-0347

L980/2:   tweeter 206-0118, mid 206-0214, woofer 206-0353

L1590:     tweeter 206-0119, mid 206-0213, woofer 206-0350

L1590/2: tweeter 206-0118, mid 206-0214, woofer 206-0361

I'm a bit surprised that drivers pattern on the L980/L1590 doesn't follow the same pattern as the L880/L1290.  I wonder if the L980 was introduced "late" relative to the L1590? (i.e I expected that it, L980/1, would have a 206-0119 tweeter & 206-0213 mid)

 

Glitch,

Thanks for your interesting comments and for the part numbers as listed.   

The L980 and AR-3a are very similar, of course, in layout and function.  Both are low-resonance acoustic-suspension designs with dome midrange and dome tweeters (both ¾-inch) and similar crossover characteristics.  A direct A-B comparison would be very interesting.  I've never read a report on a comparison between these two fine speakers, but I think there were far fewer L980s out there than AR-3as or its later iterations (AR-10, AR-58, AR98Ls, etc).  On the other hand, I did compare my L1290/2 and AR-3a speakers, and I can comment a bit on that comparison.  It was difficult to compare them, as the optimal spot for the 3a is flush in a bookshelf, and the 1290 has to be out slightly from the front wall, toed-in a bit, to be positioned optimally.  I am fond of both the 1290/2 and the AR-3a; unfortunately, the 50-year-old AR-3a dome tweeters are beginning to deteriorate, causing lower output from the domes.  Perhaps a better comparison for the L980 would be an AR-10π, AR58 or AR78 with their cloth-dome tweeters.

In the bass, the AR-3a has a slight advantage in low-frequency extension, but the differences are subtle and only noticeable on organ or electronic music or jazz with prominent kick drum or orchestral bass drum.  The 1290 isn't deficient, but it's slightly less prominent and less "warm."  Part of this difference, too, is the relative balance between the woofers and high-range drivers in the ADS vs. AR speakers.  AR's midrange and treble are more reticent, on-axis, and the output is slightly downward-sloping in the higher frequencies; this is not the case with the 1290, as it is quite uniform throughout the midrange and treble.  Therefore, the 1290 is more "forward" and brighter-sounding than the AR-3a; however, well back in the reverberant listening area, where the predominant sound is reflected, there are fewer differences in the balance of the sound between these two systems, mainly because the dispersion of the 3a's hard-dome tweeter is somewhat wider than that of the soft-dome ADS tweeter.  Therefore, the excellent power response of the AR-3a makes up for its on-axis reticence.  The AR-3a's 1½-inch dome midrange also has better dispersion than the 2-inch dome in 1290, but the clarity of the output from the ADS tweeters is just about unsurpassed.  Both of these speaker systems are so good that it would be hard to find too much fault with either system.

Therefore, I never found a favorite.  The ADS seems to bring you a bit closer to the music and there is that outstanding midrange and treble clarity.  The AR-3a is more laid-back, but it has a smooth, very natural reproduction of midrange and treble.  In the bass, the AR-3a is more solid, but the differences are subtle.  Perhaps a draw.

—Tom Tyson

[lakecat]

Quote

I had ADS 980 here that I bought at an estate sale.....only to find out the mids and tweeters were shot (fluid was dried up and were really dark instead of being clear). I removed them and spent the $225 or so dollars to get them like new by having them redone by Richard So. Was excited to get them set up and listen as I had read about them being studio monitors...rare....and being able to handle 300 watts. 

And...I was disappointed. It was too clean for my taste. I am not a musician so critical listening is not my forte but the music that I like sounded better on the 3a. The bass is more buttery and warm with the 3a and the mid was better to me. The 980 had excellent highs but again that area is not important to me but it was certainly better than the screeching L166 JBL's I had here. 

My buddy that is into audio big time bought my 980's and loves them.....so it is all in how we like to hear and the level one is at in listening to music. One note.....the woofer on the 980 is installed in a manner that is maddening to ever remove. I asked Richard So about it as I wanted to check out the crossover....and he showed me a tool he made to remove it. He said it is a real pain to remove...so I passed...:)

 

[tysontom]

On 6/25/2018 at 8:02 PM, lakecat said:

 

lakecat, 

I think your comments about the ADS L980 do reflect a common sentiment about the spectral balance of the ADS woofer, midrange and tweeter.  These are accurate and analytical dome drivers, but they have a lot of output, and this sometimes comes across as being a bit forward-sounding.  Also, some ADS woofers tend to be slightly over-damped in some instances in an effort to avoid "warmth" in the sound, and this makes the speakers seem dry and lacking in bass in some respects.  I don't sense this dryness when I listen to my 1290s,  but it may be that the 980 is that way since it was intended to be used in recording studios and high-end installations.  Also, you are going to be hard-pressed to find a woofer that can surpass the AR-3a in the region from 500 Hz down to 30 Hz or so; it is nearly perfect in this range with very uniform output and extremely low harmonic distortion.  I would love to see the measurement curves on the L980, but I'm sure it is excellent, nonetheless.  I don't know the Q of that system or its actual bass resonance (fc) frequency, but I think the latter is around 41 Hz or so, similar to the AR-3a.  I suspect that the Q is somewhere between 0.7 and 0.5 judging by the "dry" sound.  The AR-3a is 0.7 to 1.0, approximately.    

I have found that the best place to listen to ADS speakers (in general) is in a large, well-padded living room with little slap echo.  A "live" room can be difficult sometimes, but in the right room these speakers can sound great!  In any event, ADS always tried to get the most accuracy from their products, and their design and production-control methods for the dome tweeters was outstanding, and there is rarely any variation in the sound.  It is unfortunate that most of the ADS (and later a/d/s/) models did not get widespread critical acclaim and reviews in the way that AR speakers did through the years.  Julian Hirsch did give the 1290 very high marks, and Julian was basically very fond of Acoustic Research products through the years.  Overall, AR received many glowing reviews and tests, and ADS was not tested as much for some reason, yet each design was superb in its own way. 

Consider this interesting tidbit: ADS manufactured (for the most part) their drivers for the 1090, 1290 and 1590 in-house in the Wilmington, MA facility; the cabinets were made in Germany and shipped to the US!  It's amazing that this could be considered economical, but somehow it worked for ADS at the time.

--Tom Tyson

[lakecat]

Nice explanation on those 980's. Mine were set up in a 28' deep by 18' wide by 16' high cathedral ceiling room...and is sunken 3'. Tall windows on each end.

The speakers were set up one pair at a time about twenty-eight inches from floor and six feet apart...just a hint of toe in. They were about six inches out from wall behind. 

I have to add that my friend that bought the 980's....and is s big ADS fan...still prefers his 1590's.

[tysontom]

Notice any difference in this topic?  I corrected my early logo mistake: "a/d/s/ L1590 to the correct version, ADS L1590!"  ADS didn't change to the more avant garde "a/d/s/" until the late 1980s with the M-series. 

--Tom Tyson

[tysontom]

Also, check the number of "views" on this one topic!  More than 72,000!  There are very few topics that have been viewed this often.  This shows the popularity of ADS' L-series tower speakers, especially the L1590.

--Tom Tyson 

[Glitch]

On 8/5/2018 at 11:13 PM, tysontom said:

Notice any difference in this topic?  I corrected my early logo mistake: "a/d/s/ L1590 to the correct version, ADS L1590!"

Better late then never?  ?

I just reread the entire thread.  Does this add 1 to the counter?  

One thing I noticed is that the links to the .pdf files and many of the pictures are dead.  Bummer.

[tysontom]

On 8/7/2018 at 11:33 AM, Glitch said:

Better late then never?  ?

I just reread the entire thread.  Does this add 1 to the counter?  

One thing I noticed is that the links to the .pdf files and many of the pictures are dead.  Bummer.

Yes, better late than never!  I didn't realize that I could edit the actual subject line itself, but the originator has some slight latitude.   

What files do you need?  I think I dropped some files after my file load approached maximum.  I can replace any that are needed for download.

--Tom

[batchman]

And speaking of better late than never, how's this for a late comment...

I can recall at the time, there were opinions (even within ADS I think) that the L1290 could provide better imaging owing to its' narrower baffle board.

I have a set of each but have never A/B'ed them.  Never actually used the L1290s as "front", hope to in a new setup sometime maybe later this year.  I've not been tempted to unplug my L1590s for any reason what-so-ever.  Might try stacking 1290s on top for atmos height speakers (overkill, YEAH!) though ;).

Cheers,

- Jeff

 

[tysontom]

I think this ADS L1590 thread has become the most widely read topic in all of the Classic Speaker Pages!  Up above 76,000 reads, and that is amazing.  Says a lot about this remarkably fine loudspeaker, at or near the top of ADS's engineering efforts.

The 1590 woofer loafing along at relatively low power at 20 Hz.  Much more excursion left to go!  One of the hallmarks of the ADS 1590A was the robust pair of 10-inch woofers -- each with 2-inch voice coils and lots (5/8") voice-coil overhang -- was deep bass with very low harmonic distortion.  This speaker was one of the best at reproducing clean deep bass with low distortion.

--Tom Tyson

[batchman]

On 11/29/2018 at 1:43 PM, tysontom said:

This speaker was one of the best at reproducing clean deep bass with low distortion.

 

And yet, on that score,  it cannot hold a candle to the L980 - whose 12", with the power handling, cabinet volume and excursion, easily blows out said candle ;).

That's why my system includes both,  and a 1/2hp a/d/s sub for good measure (for those LFE moments) LOL.

Cheers,

- Jeff

(OK, I confess - I'm a bass player )

[tysontom]

On 12/15/2018 at 8:24 PM, batchman said:

 

And yet, on that score,  it cannot hold a candle to the L980 - whose 12", with the power handling, cabinet volume and excursion, easily blows out said candle ;).

That's why my system includes both,  and a 1/2hp a/d/s sub for good measure (for those LFE moments) LOL.

Cheers,

- Jeff

(OK, I confess - I'm a bass player )

Huh?  Are you saying that the L980, with its higher-resonance enclosure and single 12-inch woofer, has great power-handling, etc than the L1590?  That does not make sense, but it's entirely possible that I didn't understand what you were trying to say.

--Tom 

[engfant]

First for 2019!

 

So anyone ever heard of the A/D/S AVT 148 Video Tower ?? I can't find really anything on them.

[speyflyfisher]

I own a pair of 1590s and was curious how to pull the woofer-  is there any issue with spider sag on these woofers after 30+ years?  Has anyone explored adding any additional internal bracing/damping to the sides?  Also had considered putting on neoprene, foam, etc around mid/his.  Thoughts??  

Edited January 12, 2019 by speyflyfisher
add sentence

[batchman]

On 12/23/2018 at 9:45 PM, tysontom said:

Huh?  Are you saying that the L980, with its higher-resonance enclosure and single 12-inch woofer, has great power-handling, etc than the L1590?  That does not make sense, but it's entirely possible that I didn't understand what you were trying to say.

--Tom 

 

Well, as a bass player of over 40 years, I can tell you that the L1590s produce a nice smooth bass line, very very nicely.

But the L980s move air like the 1590s cannot even dream of.  They can break things .  I run both currently, with 200wrms into each path biamped.  Power handling spec is the same (yes, I exceed it some) but the result is different.  I suspect the damping factor in my amps are contributing to both success at that, and the result.

I will say you can hurt the 980 woofers with too much sub-synth content, but only a bass player (deef) would do that ...

Cheers,

- Jeff

 

 

[tysontom]

30 minutes ago, batchman said:

 

Well, as a bass player of over 40 years, I can tell you that the L1590s produce a nice smooth bass line, very very nicely.

But the L980s move air like the 1590s cannot even dream of.  They can break things .  I run both currently, with 200wrms into each path biamped.  Power handling spec is the same (yes, I exceed it some) but the result is different.  I suspect the damping factor in my amps are contributing to both success at that, and the result.

I will say you can hurt the 980 woofers with too much sub-synth content, but only a bass player (deef) would do that ...

Cheers,

- Jeff

 

 

What you are saying isn't possible.  Maybe it feels like more bass to you, and perhaps the 980 is more efficient or has a lower impedance (making it louder for the same  volume control setting) but the two 10-inch woofers in the 1590 can move as much air as a single 15-inch woofer, and we both know that a 15-inch woofer is larger and can move more air than a 12-inch woofer, all things being equal (voice coil excursion, etc).  The 980 may also have a bass rise down close to resonance, and this would make it seem to have more bass output, but this is not like ADS to have this problem.  The 1590 woofers also have a lower resonance than the 980, so the 1590s can also get lower in bass.  Both the 1590 woofers and the 980 woofers use a 2-inch-diameter voice coils with about the same linear excursion.  So do the math: the 1590 is inherently more potent in the bass than the 980.  I'm not saying that for one reason or another, you are not actually hearing more bass from the 980; I'm just saying that technically, the 980 cannot move as much air as the 1590.  The 980 is more akin to the Acoustic Research AR-3a in bass output; both of those speakers are closer in performance with about the same resonance, same woofer size, etc.

More importantly, why would ADS have ever designed a large bookshelf-type speaker (studio-type) in their product line that costs significantly less than the 1590 to have better bass output?  That doesn't make sense, and ADS would have been ridiculed in the industry if this were the case.

--Tom  

[batchman]

OK, I'll bite - you have me curious.  My impressions are from owning both, although some of the arguments are moot as at extended levels either box will drive the tweeters into protection - the limiting factor.  I'd be doing A/B listening comparisons right now to confirm (I am actually wired for that), but my wife is home ;).  In my system, if I were running only the 1590s, I would want a subwoofer.  With the 980s, I run a sub only for protection...

I had attributed the difference to excursion, curious to hear they're similarly spec'ed.  Always appeared visually different to my eye, and recall the 980 as readily able to blow out a match ;).

As to the ear, the other aspect is cabinet volume vs driver area - 980 has the advantage there:

L980 = cabinet volume 3838in^3, driver area 113in^2 = ~34in^3 per driver in^2

L1590 = cabinet volume 4227in^3, driver area 157in^2 = ~27in^3 per driver in^2

I presumed the dimensions of the cabinet should matter too, as there is wave action (and reaction) inside the box as well.  Also please realize the power handling for the 1590 was across two drivers, same rating on L980 for *one*.  Granted, it's probably commonality in the crossovers that lead to the consistent rating, if you are sure the voice coils are that similar...

Granted frequency specification is similar (I recall a modest edge to L980 LowF) and I do not have matching A/B documentation, but the L1590 spec's down to 28db at +/-3dB.  Attached is a sweep from an L980...

As to pricing, I think the market was not really seeking office-fridge sized bookshelves ;), and the stands added some to the equation.  I believe studio reference was the big target for the L980s.  The real market was towers, and buying new then the 1290 would have been the value leader with the wifely acceptability thrown in.

Cheers,

- Jeff

 

L980 curves.pdf

[batchman]

On 1/11/2019 at 8:41 PM, speyflyfisher said:

I own a pair of 1590s and was curious how to pull the woofer-  is there any issue with spider sag on these woofers after 30+ years?  Has anyone explored adding any additional internal bracing/damping to the sides?  Also had considered putting on neoprene, foam, etc around mid/his.  Thoughts??  

Welcome to the discussion!

The cast baskets on ADS woofers seem to age very well, see attached.  Removing them will require a stout hook to grab through a screw hole.

The cabinets are well designed also.  I've had some boxes that "contribute to non-linearity", but never from ADS (or a/d/s for that matter).

I have heard of some success with adding acoustic foam to the front baffle, but not been tempted (yet) to try that myself. 

Cheers!

- Jeff

 

[tysontom]

>OK, I'll bite - you have me curious.  My impressions are from owning both, although some of the arguments are moot as at extended levels either box will drive the tweeters into protection - the limiting factor.  I'd be doing A/B listening comparisons right now to confirm (I am actually wired for that), but my wife is home ;).  In my system, if I were running only the 1590s, I would want a subwoofer.  With the 980s, I run a sub only for protection...

Jeff,

I think you are confusing deeper bass with "more" bass, as in the 40-80 Hz range, such as double bass or guitar bass or what have you, and it sounds to me like you are getting a peak output in the 980 in that region above resonance, and likely you are not getting this same bump in output in the 1590.  And by the way, you would never need a subwoofer with a properly working 1590, not with its bass extension.  That said, I think the 1590 has a lower "Q" (more damping) at resonance than the 980, thus making the bass seem to you to be a bit weaker when compared to the 980 side-by-side.  This is the only explanation I can give you for you feeling that the 980 is stronger in the bass than the 1590.  If you carefully matched the output level from both the 980 and 1590 speakers (only one channel at a time) at around 300 Hz, and then swept frequency downward with a audio oscillator (a high-quality one such as a Hewlett-Packard instrument), you would see that output continues further into the deep bass with greater linear output in the 1590 than with the 980; it's that simple. 

  

If you are driving the tweeters into protection with a 200-watt amplifier, you are likely clipping the amplifier, causing excessive output into the tweeters; you are essentially over-driving the amplifier.  The 1590/2 can easily handle 500-watt peaks, and the 980 can handle 300-watt peaks, so there is no reason to think the speakers are in protection mode with this amplifier setup unless the amp is over-driving.  You might also have your bi-amp setup incorrectly wired; in any event, there are more opportunities for problem with bi-amping something like this than by simply using a larger single amplifier through a single input connection.  Most importantly, bi-amping does not improve sound quality; it simply allows more power to be applied to the speaker.  Bi-amping also increases the opportunity for mistakes and out-of-phase wiring issues.

>I had attributed the difference to excursion, curious to hear they're similarly spec'ed.  Always appeared visually different to my eye, and recall the 980 as readily able to blow out a match ;).

Yes, the voice coils on both of these systems are very similar, and both have about the same excursion.  To keep efficiency at decent levels, ADS would never have gone overboard on the excursion travel on the 12-inch woofer in the 980.  If they had used a longer voice coil to increase the excursion to 1-inch, for example, the efficiency of the system would have dropped by half, and the midrange and tweeter drivers would not properly match the efficiency of the woofer.  It would make no sense whatsoever to design a speaker in that fashion.

>As to the ear, the other aspect is cabinet volume vs driver area - 980 has the advantage there:

L980 = cabinet volume 3838in^3, driver area 113in^2 = ~34in^3 per driver in^2

L1590 = cabinet volume 4227in^3, driver area 157in^2 = ~27in^3 per driver in^2

This argument isn't valid because it does not take into account the individual speakers' parameters, such as damping, free-air resonance, and so forth.  Remember, the two 10-inch 1590 woofers have the approximate radiation area of a single 15-inch woofer vs. the 12-inch woofer in the 980, and with similar excursion, the displacement-volume numbers are in favor of the 1590

>I presumed the dimensions of the cabinet should matter too, as there is wave action (and reaction) inside the box as well.  Also please realize the power handling for the 1590 was across two drivers, same rating on L980 for *one*.  Granted, it's probably commonality in the crossovers that lead to the consistent rating, if you are sure the voice coils are that similar...

>Granted frequency specification is similar (I recall a modest edge to L980 LowF) and I do not have matching A/B documentation, but the L1590 spec's down to 28db at +/-3dB.  Attached is a sweep from an L980...

I don't understand what you mean by "wave action and reaction inside the box."  That is a new one on me.  The power-handling on the L1590/II is 500 watts, and the 980 is 300 watts, peak.  The earlier spec for the first 1590, using slightly different woofers, was also 300-350 watts peak, but the later series II version is 500 watts.  The 980 has always been 300 watts peak maximum power.  Note, again, that the low-frequency edge is clearly in the 1590's favor with its lower bass resonance!  This is the physics of what is happening; it's not my conjecture.

By the way, the response graph you attached is not the (acoustical) output of an ADS L980.  It is the electrical current or voltage across the crossover.  It shows the energy path through the crossover, but not the acoustical output of the speaker itself.  It therefore does not show you anything about the low-frequency output of the speaker itself.

>As to pricing, I think the market was not really seeking office-fridge sized bookshelves ;), and the stands added some to the equation.  I believe studio reference was the big target for the L980s.  The real market was towers, and buying new then the 1290 would have been the value leader with the wifely acceptability thrown in.

The ADS 980 was designed to be a competitor with the likes of Acoustic Research's AR-3a, AR10Pi, AR-11, Large Advent and so forth, but it was marketed to be a "studio monitor," to enhance its place in the speaker market place, and insofar as it was priced slightly above those speakers.  It was somewhat larger to get a low bass resonance, which was set a around 40-42 Hz, similar to the AR-3a/AR-11.  The 980 was also priced much lower than the 1590 as well, so you would expect it to not perform quite as well.

Let me finish my comments by saying that I don't doubt your admiration for the 980.  It is a wonderful loudspeaker, but you should understand that the 980 is not equal to the 1590 in low-bass output, extension or low distortion.  I have always liked the sound of the 980, and I think it is one of ADS's better efforts.  Compared with the 1590, it might be close, of course, but not equal and certainly not superior. 

I have spent this time simply to try to set the facts straight in this discussion about these two speakers.  I am not trying to criticize or dispute your impressions, but I wanted to be sure that anyone else reading this would realize that the L1590 is a more potent system over a wider range, for good reasons, than the L980.

--Tom Tyson

[batchman]

Hi Tom,

It's late and I lack the time to line-item reply, but my suspicion here is it could easily be "all about the room".  Thanks for the treatise, but I will have to agree to disagree on bi-amping not improving sound quality (try it, you'll like it!).  My 1590s did not fully impress until I did that, with no other changes - same amp in bridge mode switched to 4 channel, and this amp's stats are unusually linear in both cases.  I will stand corrected on my sweep example - which by the way was done at ADS - looking at it in clear light that surely must be the crossover, anechoic rooms aside.

No worries on the proper deployment of bi-amping, and no worries about headroom or clipping (dbx BX-1 (x2); clipping is just not going to happen, and damping factor is in rarified space) - it's an output vs thermal thing - the tweeters are definitely the first to fold in high output situations.  I realize this is the internet, and on the internet no-one knows I'm a dog, but there's only so much you can ask of a driver this size.  I presume this is why the larger format ADS speakers used multiples.  Sigh, if only those could survive spousal acceptance...

I will say that as original owner of this particular pair of L-980s (series 1, with series II polyswitches) I can say in my room, they outperform the 1590s (also series 1) on imaging (room issue for sure) and in low end (possible room issue, but who can say).  I'll go on to say in every room I've enjoyed them in, they have always exceeded expectations on the low end.  Although I've owned them ~10 years, the 1590s are still in their first room.  Please do not take anything I'm saying as a dig on the 1590s, which I treasure, but on the other hand the specsmanship is close enough that deployment probably dominates results.

As to power handling, I have always understood ADS's ratings to be WRMS and was not aware of the difference in the 1590 Series II, but suspect either aggressively marketed or perhaps less conservative ratings considering the I & II (of both lines) are made of essentially the same stuff.  Similarly I will offer conjecture that the list price difference was probably due to the added driver, added costs due to the longer cabinets, and what the market would bear in the two very different formats.

As a bass player (functional, not professional), I understand distortion, and further, non-linearities in sound systems and most importantly, rooms.  That's not the issue.  I will add that as I keep three different amps for gigging, and having owned and played through many others, when it comes to drivers - and cabinets - size matters.  Again, perhaps this is my particular spectrum of deefness , but I'll stand by *my* 980s outrunning *my* 1590s in *my* room.

I'll look forward to proving that to myself, again, when I can "get the room" - which sadly does not happen often enough...  (I'll have to re-try the match test)

Thanks, regards, and do have a good night,

- Jeff

PS - IMHO it's high current that these speakers need...

 

Edited January 26, 2019 by batchman
toned down some beer-driven rhetoric, updated some tech

[mikethetike]

Yes ADS speakers are very dear to a lot of peeps. This is the 2nd forum that is still going for more than a decade????? Wow

So the debate is centering on 980 versus 1590. I have the 980, LOVE em, and over time have acquired 2 pristine 980 12" woofers. Question: should I copy the 1590 format, 2 woofer towers,  or use the extra 12"ers as subs. I am not a fan of pounding bass but I have the Marantz LFC that is designed to soften sub pounding, "be a good neighbor".

I haven't heard the 1590's yet but due to selling our house and now in a smaller townhome I am listening to 2 sets of Braun 715's. There is bass in this set up, oh yah, and I use the LFC to tame the booming. My present power amp is a Butler Audio TDB 5150.

I also have a pairs of Braun LS120, ADSL8e's, SAT6's 400e's and  I hope to pair my 980's in some kind of combo with some of that I own.